The Clinical Core (Core B) of the Penn Udall Center has four key functions: 1) To recruit patients with Parkinson's disease (PD), PD with dementia (PDD) dementia with Lewy bodies (DLB), and normal control subjects for the Udall Center's projects; 2) To develop strategies for outreach to minorities and recruit them for participation in studies; 3) To collaborate with the Administrative and Educational Core (Core A) in educating residents and fellows, health care professionals and the PD community; 4) to collaborate with the Statistical Core (Core D) to maintain a secure, compliant, state-of-the-art relational database; and 5) to join with the Neuropathology, Biomarker and Genetics Core (Core C) in collaboration with other Udall Centers on clinical characterization and sample collection. Patients and controls recruited to Core B will consent to donate blood and cerebrospinal fluid (CSF) during life, and brain tissue at death, for the identification of potential biomarkers of PD-related neurodegeneration, including peripheral biochemical analytes and genetic markers in blood and CSF. Participants in the Penn Udall Cohort will have annual evaluations to the time of death. The principal source of patients is the Parkinson's disease and Movement Disorders Center (PD&MDC) of the University of Pennsylvania, located at the Penn Neurological Institute at Pennsylvania Hospital. The PD&MDC is one of the largest referral sites in the northeastern US for the diagnosis and treatment of PD and other movement disorders.